1. Field of the Invention
The invention relates to a membrane micropump, and in particular, to a membrane micropump which comprises a vibration chamber with flow guide.
2. Description of the Related Art
There are varieties of micropumps, and they are substantially distinguished into mechanical types and non-mechanical types. The mechanical micropump, is not limited by specific work fluid, and it can be designed differently according to different types of actuators and valves. The non-mechanical micropump is limited by the specific work fluid. For example, electrophoretic micropumps (U.S. Pat. No. 6,932,580) and electroosmosis micropumps (U.S. Pat. No. 6,770,183) can only used to pump work fluid with an electric charge or with polar molecules. Additionally, the non-mechanical micropump comprises relatively slow flow velocity and requires relatively high work voltage to operate.
The mechanical micropump comprises mostly membrane-displacement pumps (membrane pump in short) such as U.S. Pat. No. 6,261,066, which is also one of the main-stream research areas in mechanical micropump technology. Within the membrane micropump in the sub-component of the actuator, the piezoelectric actuator becomes the main issue of study. In another aspect, in the classification of the valve, the membrane micropump is distinguished into a valve type (U.S. Pat. No. 6,874,999) and a valveless type (U.S. Pat. No. 6,203,291). The valveless membrane micropump comprises a simple structure, non-moving parts and requires no extra energy consumption. Furthermore it does not become exhausted and clogged; therefore, it has recently become the main topic of study in this academic field.
However, all types of conventional valveless membrane micropump are focused on the design of the rectifier, not on the interior structure of the vibration chamber. Here, the vibration chamber is the main developing portion of the entire valveless membrane micropump, and the interaction of the vortices exists within the vibration chamber. In detail, the development of the vortices comprises characteristics highly related to the efficiency of the membrane micropump. As described, because the conventional membrane micropump is not designed according to the development of the vortice, there must be a lot of potential to improve the efficiency of the membrane micropump.